Stopper



FIG. 1 is a perspective view of my stopper design taken from above;

FIG. 2 is a perspective view of my stopper design taken from below and 180° about its periphery from FIG. 1;

FIG. 3 is a plan view of my stopper design;

FIG. 4 is a bottom view of my stopper design;

FIG. 5 is a side elevation of my stopper design, it being understood that a side elevation taken from 180° about its periphery will be a mirror image of this FIG. 5;

FIG. 6 is a side elevation of my stopper design taken from the left of FIG. 5; and,

FIG. 7 is a side elevation of my stopper design taken from the right of FIG. 5. 

The ornamental design for a stopper, as shown and described. 